Executive or legislative commissions examine the possible consequences of climate change for a state and the costs and benefits associated with addressing them, and develop recommendations for appropriate policies.

Several states have begun implementing either mandatory or voluntary reporting of greenhouse gas emissions from major sources. The Climate Registry is a non-profit organization that aims to measure and publicly report greenhouse gas emissions in a common, accurate, and transparent manner consistent across industry sectors and borders.

By law states have the option of either following federal emissions standards for cars and light trucks or following California's standards. Other states that have already adopted or are in the process of adopting the California standard include Arizona, Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington.